Photodevelopment of silver halide print-out material



United States Patent 3,418,122 PHOTODEVELOPMENT 0F SILVER HALIDEPRINT-OUT MATERIAL Ralph S. Colt, Rochester, N.Y., assignor to EastmanKodak Company, Rochester, N.Y., a corporation of New Jersey No Drawing.Filed Aug. 23, 1965, Ser. No. 481,918 17 Claims. (Cl. 96--63) ABSTRACTOF THE DISCLOSURE Process for providing a direct-print material which ischemically developable to a visible image comprising imagewise exposinga fine-grain silver halide photographic print-out material comprisingsilver halide grains which have trivalent metal ions occluded therein,repressing the print-out ability of the silver halide by heating to atleast 300 F. and exposing said silver halide to light to produce avisible image.

This invention relates to the preparation of photodeveloped images onsilver halide sensitized photographic materials and particularly to amethod of producing such images on normally nonphotodevelopableprint-out materials.

It is well known that photographic prints of good density and contrastcan be produced on silver-sensitized coatings, without chemicaltreatment, by the so-called print-out process which involves theimagewise photolysis of silver salts. In this process, the coating isexposed sufiiciently to print out a visible silver image. Historically,such print-out silver images were the first to be produced in thedevelopment of the silver halide photographic process. However,relatively prolonged exposures are required for producing print-outimages, and moreover, such images are quite unstable. The images are notfixed and background density prints out when exposed to roomlight.

The relative simplicity of the print-out process, which requires no wetprocessing and obviates drying, has stimulated a search for newformulations and/ or photographic processing procedures which wouldretain the fundamental advantages while providing improved sensitivity,greater image stability, and more rapid access to the finishedphotograph.

A recent development has been the direct print process in which a muchlower image exposure than that required for the conventional print-outprocess, is used to generate a latent image which is made visible by asubsequent uniform light exposure. High intensity light of shortduration is used to make the image exposure, and light of lowerintensity and longer duration is used for the second exposure which istermed the latent image intensifying (latensifying) or photodevelopingexposure. The efliciency of latensification or photodevelopment in thedirect print process can be improved in a number of ways, particularlyby lowering the intensity of the light employed. This unfortunatelyresults in prolonged photodevelopment times. Such photodeveloped images,like print-out images, are not stable to prolonged exposure to furtherviewing light and the density difference between background and imagedecreases as further exposure occurs.

Photodevelopable direct print materials have already proved very usefulin many image-recording applications. Still more widespread commercialapplication awaits development of faster procedures which will providethe photodeveloped image more rapidly.

It is accordingly an object of this invention to provide a newphotodevelopment process which quickly provides silver images of highstability to light and of good contrast quickly from latent imagesexposed on normally nonphotodevelopable silver halide sensitizedmaterials.

It is another object of this invention to provide a new rapid directprint process for use with silver salt sensitized photographic emulsioncoatings to provide photodeveloped images of good density and contrast.

It is another object of this invention to provide a new direct printprocess that uses a non-optical physical treatment after latent imageformation to permit photodevelopment of normally nonphotodevelopablelatent images.

It is another object of this invention to provide a new direct printprocess that can be utilized to rapidly prepare visible images.

It is likewise an object of this invention to provide a new direct printprocess suitable for use with print-out silver halide systems.

It is a further object of this invention to provide a novel direct printphotodevelopment process that will operate efiiciently over a wide rangeof intensities of image exposure.

It is a still further object of this invention to provide a novel directprint process that permits rapid photodevelopment by using lightintensities much higher than the light intensities used for latent imageformation.

These and other objects of the invention are attained by means of thisinvention as described more fully hereinafter.

In accordance with the invention a silver halide printout material isimagewise exposed to form a latent image, the exposed silver halideheated to at least about 300 F., and thereafter the heated silver halideis uniformly exposed to light for a sufficient time to produce a visibleimage. The silver halide print-out material utilized in the presentprocess is the type that is capable of being exposed to light to form alatent image that is chemically developable to a visible image and whichlatent image is incapable of being photodeveloped by uniform exposure toa visible image of substantial discrimination (e.g., D -D =less than .1)at temperatures up to 250 F.

In accordance with the present process a print-out material thatnormally would uniformly fog if uniformly exposed to light after animagewise exposure can be used to prepare light-stable visible silverimages by heating to temperatures of at least about 300 F. prior to thephotodevelopment or photolysis step. The heating step in the presentprocess represses the usual printing out of unexposed or non-image areas(D the original recording sensitivity of the silver halidebeinginactivated by such heating. The optimum temperature and timeinterval to which the silver halide print-out material is heated inaccordance with the present process can be readily ascertamed by one ofordinary skill in the art by simply moditying such variables until animage having optimum or desirable discrimination density is obtainedafter photodevelopment. Temperatures of at least about 300 F. utilizedand preferably at least about 350 F. The upper extremes of the heatingconditions utilized in the present process can also be readilyascertained by one of ordinary skill in the art, such factors as thebreaking down or charring of the support of the photographic element orthe vehicle for the silver halide being practical considerations.

The initial imagewise exposure is to light in the spectrum range inwhich the silver halide is sensitive sufiicient to form a latent image(invisible image) in the silver halide material, but insutficient tocause the silver halide to print out. Such an image exposure can beeffected with high or low intensity light. Such exposure conditions canbe readily ascertained and vary widely with the type of silver halidematerial utilized. The latent image so formed is capable of beingchemically developed to a visible silver image with known photographicdeveloping compositions.

The final step in the present process is a uniform or over-all exposureof the image-exposed and heated silver halide material to light in thespectrum range in which the silver halide was initially sensitive(typically about 2500-5700 Angstrom units such as ordinary daylight,tungsten light, fiuoroescent light, etc.). This step is aphotodevelopment or photolysis step and is utilized to develop thelatent image formed in the initial imagewise exposure to a visiblesilver image of substantial discrimination. Such photodevelopment can becarried out during or after the heat treatment step. The development ofthe unexposed or non-image areas is repressed by the aforedescribedheating step.

A wide variety of silver halide systems that print out, but which cannotbe photodeveloped after a latent image exposure to a visible image ofsubstantial discrimination on uniform exposure to light when heated totemperatures up to 250 C., can be utilized. Light-developabledirectprint silver halide systems of the type typically exposed to ashort duration, high-intensity light source to form a latent image andthereafter photodeveloped by exposure to a light source of longerduration and lower intensity than the imagewise exposure are notutilized in the present process. The present silver halide print-outsystems are composed of fine-grain silver halide more typically havingan average silver halide grain size of less than about .2 micron andgenerally ranging from about .01 to .2 micron.

A particularly useful photographic system that can be utilized in theprocess of the invention is a radiationsensitive silver halide print-outsystem containing unfogged silver halide grains formed in the presenceof a trivalent metal ion in an acidic media, such silver halide systempreferably having contiguous to the trivalent metalcontaining silverhalide grains a halogen acceptor.

In preparing such photographic systems, trivalent metal ions are used inthe precipitation or formation of the silver halide. Silver halidecrystals are formed with trivalent ions on the inside of the crystals,i.e., silver halide crystals with trivalent ions occluded therein.Typical suitable trivalent metal ions include those of bismuth, iridium,rhodium and the like. Bismuth ions are particularly useful. Thetrivalent metal ion can be suitably added with the water-soluble silversalt (e.g., silver nitrate) or the water-soluble halide (e.g., sodium orpotassium iodide, bromide or chloride) that are conventionally reactedto prepare or precipitate photographic silver halide. Likewise, thetrivalent ions can be introduced into the silver halide precipitationvessel with a hydrophilic colloid such as gelatin. The trivalent metalions can be added to the system as water-soluble inorganic salts, asorgano-metallic materials, as complexes, or any other form of materialthat results in the availability of trivalent metal ions during theformation of silver halide. The amount of trivalent metal utilized canbe widely varied, although at least about 1x10 and more generally 1 10-to 2, mole percent based on the silver halide is used.

In preparing the print-out silver halide with trivalent metal ions, thewater-soluble silver salt and the watersoluble halide are reacted toprecipitate the silver halide under acidic conditions. The pH of thesilver halide precipitation is typically less than 6 and preferably lessthan 5. Such acids as phosphoric, trifluoracetic, hydrobromic,hydrochloric, sulfuric and nitric are typically utilized in the silverhalide precipitating media to maintain acidic conditions.

Suitable silver halides used in preparing the photographic elementsprocessed in accordance with the invention include silver chloride,silver bromide, silver bromoiodide, silver chloroiodide, and silverchlorobromiodide. The silver halide preferably contains at least 50%bromide, less than 10% iodide and less than 50% chloride on a molarbasis. Both silver halide that forms latent images predominantly on thesurface of the silver halide crystal or those that form latent imagespredominantly inside the silver halide crystal, such as those describedin Davey and 4 Knott, US. Patent 2,592,250 issued Apr. 8, 1952, can beused in the materials of the present invention.

The silver halide used in preparing the photographic elements processedin accordance with the invention is typically utilized in an emulsion ordispersion containing a colloidal material. Gelatin is preferably usedas the colloidal material, although other colloidal materials such ascolloidal albumin, cellulose derivatives or synthetic resins, forinstance, polyvinyl compounds can also be used. Mixtures of suchdispersing agents in a wide range of proportions can beutilized,'typical of such mixtures being mixtures of gelatin and anacrylate-acrylic acid copolymer. Such emulsions can contain conventionaladdenda such as coating aids, plasticizers, sensitizing dyes, hardeners,etc.

'In addition to silver halide emulsions, vacuum deposited photographicsilver halide substantially free of conventional vehicles, binders ordispersing agents can be processed in accordance with the invention.Such vacuum deposited silver halide can be utilized in accordance withthe invention by incorporating the halogen acceptors in a coating orlayer contiguous to the vacuum deposited light-sensitive material.

The silver halide utilized in the present instance is unfogged. Suchsilver halide contains no visible or developable latent image. Thesilver halide is sensitive to electromagnetic radiation such as lightand x-ray.

A wide variety of halogen acceptors can be utilized in the silver halidesystems processed in accordance with the invention. Such materials arewell known to those skilled in the photographic art and areconventionally added to light-developable, direct print silver halideemul- SlOIlS.

Nitrogen-containing halogen acceptors are particularly useful inpreparing the silver halide systems processed in accordance with theinvention. Suitable nitrogen-containing halogen acceptors used can berepresented -by the formulas,

wherein: -R, R and R can each be hydrogen atoms, alkyl radicals, arylradicals, including substituted alkyl and aryl radicals, or acylradicals (e.g.,

wherein R is a hydrogen atom, an alkyl radical or an aryl radical); \Rcan be a nitrogen-containing radical such as an amino radical or athiocarbamyl radical, including substituted amino and thiocarbamylradicals; and D represents the necessary atoms to complete aheterocyclic nucleus generally having 5 or 6 atoms including at leasttwo nitrogen atoms and at least one divalent radical having the formula,

wherein X can be a sulfur atom, an oxygen atom, a selenium atom or animino radical (-=NH). When a nitrogen atom comprising D or R is attacheddirectly to the nitrogen atoms of the above formulas, at least onehyrogen atom is attached to at least one of such nitrogen atoms of thehalogen acceptor. The amino radical for substituent R can be representedby the formula,

wherein R and R can each typically be such substituents as hydrogenatoms, alkyl radicals, aryl radicals or acyl radicals as described abovefor R and R The thiocarbamyl radical for substituent R can berepresented by the formula,

wherein R and R can be the same substituents as R and R or aminoradicals.

Particularly useful nitrogen-containing halogen acceptors used in theinvention can be further represented by the following subgenericformulas:

wherein: R R R R R R R R R and R can each be hydrogen atoms, al'kylradicals, aryl radicals or acyl radicals as described above for R, R andR E can be a sulfur atom, an oxygen atom, a selenium atom or an iminoradical; and Q and Z can be the necessary atoms to complete aheterocyclic nucleus generally having 5 or 6 members. Q and Z typicallyare the ,necessary atoms to complete such moieties as a triazole-thiol,a mercaptoimidazole, an imidazolidine-thione, a triazinethiol, athiobarbituric acid, a thiouracil, a urazole including a thiourazole andthe like heterocyclic moieties.

With respect to the above formulas of nitrogen-containing halogenacceptors: the aryl radical substituents are those of the naphthyl andphenyl series, and include such common substituents as alkyl groups,halogen atoms, acyl radicals and the like; the alkyl radicalsubstituents typically can contain 1 to 20 carbon atoms and moregenerally 1 to 8 carbon atoms, and can be substituted with such radicalsas aryl radicals, halogen atoms, acyl radicals and the like.

Typical halogen acceptors of the thiourea type represented by Formula Aand Formula B are disclosed in copending Kitze application, now US.Patent No. 3,241,- 971 issued Mar. 22, 1966; and in copending Fixapplication, now US. Patent No. 3,326,689. Typical halogen acceptors ofthe hydrazine type represented by Formula C are disclosed in Ives, US.Patent 2,588,982, issued Mar. 11, 1952. Typical halogen acceptors of thetype represented by Formula D are the urazole and thiourazole halogenacceptors disclosed in Bacon and Illing'swo'rth application, U.S. Ser.No. 406,186 filed Oct. 23, 1964.

'Examples of specific nitrogen-containing halogen acceptors that areuseful in the invention are set out below.

1 ,3-dimethyl-Z-imidazolidinethione Z-imidazolidinethione1-phenyl-5-mercaptotetrazole Thiosemicarbazide Tetramethylthioureap-dimethylaminobenzaldehyde-thiosemicarbazone l-isopentyl-Z-thiourea1-(2-diethylaminoethyl) -1,2,5,6-tetrahydro-l-3,5-triazine-4-thiol 1,2-bis( 1,2,5 ,6-tetrahydro-l ,3,5-triazine-4-thiol) ethanel-phenyl-Z-thiourea 1 ,3-diphenyl2-thiourea 4-thiobarbituric acid2-thiouracil l-acetyl-2-thiourea 1,3-dibenzyl-2-thiourea 1,l-diphenyl-Z-thiourea l-ethyl-1-(a-naphthyl)-2-thioureaZ-mercaptoimidazole 5-selenourazole Hydrazine Phenylhydrazinehydrochloride 2,5-dichlorophenyl hydrazine1-phenyI-Z-imidazolidinethione 4,5-diphenyl-4-imidazolidine-Z-thione1-methyl-2-mercaptoimidazole l-n-butyl-l ,2,5 ,6-tetrahydrol 3 ,5-triazine-4-thiol p-toluene sulfonyl hydrazine Hexylhydrazine Thioureal-methyl-Z-imidazolidinethionc D-mannose thiosemicarbazoneMorpholino-Z-propane thiosemicarbazone D-galactose thiosemicarbazoneUrazole 3-thiourazole 3,5-dithiourazole 3,5-dithiourazole hydrazine salt4-aminourazole hydrazine salt 3,5-dithiourazole hydrazine salt Urazolesodium salt 4-(1-naphthyl)urazole 4-ethylurazole l-phenylurazole4-phenylurazole l-butylurazole 1-octylurazole 4-butyl-3,5-dithiourazole1,4-diphenylurazole 1,4-dibutylurazole 1,4-dibutyl-3,S-dithiourazole1,4-diphenyl-3,S-dithiourazole 1-ethyl-4-phenylurazole 1-ethyl-4phenyl-3,5-dithiourazole 3-thio-5-iminourazole p-tolyhydrazinehydrochloride u-naphthylhydrazine a-benzyl-a-phenylhydrazine Such ureas,which include thioureas, urazoles, etc., as well as cyclic formsthereof, are merely illustrative halogen acceptors.

Other typical halogen acceptors that can be used in the inventioninclude stannous salts such as stannous chloride as disclosed in Hunt,US. Patent 3,033,678 issued May 8, 1962; aromatic mercaptans such asthiosalicylic acid; hydroquinones such as hydroquinone,chlorohydroquinone, gentistic acid and t-butylhydroquinone; catecholssuch as phenyl catechol and t-butylcatechol; paminophenols such asN-methyl-p-aminophenol sulfate; 3-pyrazolidones such as1-phenyl-3pyrazolidone, 4-methyl-l-phenyl-B-pyrazolidone and1-phenyl-4,4-dimethyl-3- pyrazolidone; phenylenediamines; nitriles;phenols; glycine; sodium sulfite; alkaline materials such as borax,alkali metal hydroxide, etc.; and the like halogen acceptors well knownto those skilled in the art.

The concentration of halogen acceptor utilized in the emulsions of theinvention can be widely varied in accordance with usual practice.Usually, about .01 to mole percent, and more generally about .1 to 25mole percent, based on the silver halide in the emulsion is utilized.

The halogen acceptors are utilized contiguous to the silver halide inthe present photographic system. Such halogen acceptors can beincorporated in the same photographic layer as the silver halide such asin the same emulsion layer, or in a layer adjacent to the silver halide.

The photographic silver halide system of the inven tion can compriselayers coated on a wide variety of supports in accordance with usualpractice. Typical suitable supports include paper, polyethylene-coatedpaper, polypropylene-coated paper, cellulose acetate film, polyvinylacetal film, polystyrene film, polyethylene terephthalate film, andrelated films of resinous materials, as well as glass, metals andothers.

The following examples illustrate preferred embodiments of theinvention.

Example 1 A radiation-sensitive gelatino silver chlorobromide (5 molepercent chloride and 95 mole percent bromide) photographic emulsionhaving an average grain size of about .06 micron was prepared by slowlyadding simultaneously an aqueous solution of silver nitrate and anaqueous solution of alkali metal halides to an agitated aqueous gelatinsolution containing 122 mg. of bismuth nitrate pentahydrate per silvermole at 60 C. at a pH of about 2.0 adjusted with nitric acid. About 5.0mole percent of the halogen acceptor dithiourazole hydrazine salt, basedon the silver, was added to the emulsion and thereafter the emulsion wascoated on a photographic paper support. The resulting preparedphotographic element was a print-out paper that can be utilized toprepare visible images without a photodevelopment or chemicaldevelopment step by exposure to suflicient light.

(A) High intensity exposure to produce visible image directly.Aprint-out image was obtained by image exposing a sample of the preparedphotographic element to tungsten illumination of 400,000 foot-candleseconds (5 minutes to 1380 foot-candles). A reflection density of 1.44was produced by photolysis under roomlight conditions. An area of thesame photographic element which was not exposed to light had areflection density of 0.09. The image discrimination of the exposedphotographic element is 1.35 density units (1.44-0.09).

(B) Latent image exposure+heat treatment-i-photodevelopment to producevisible image.Another sample of the above-described photographic elementimage-exposed in accordance with the invention to tungsten illuminationto give an exposure of 240 foot-candle seconds (20 seconds to 12foot-candles). No visible image on the image-exposed photographicelement was apparent. The resulting sample with an area having thislatent image exposure and an area with no exposure was heated by holdingit in contact with a metal platen at 530 F. for 2 seconds in the dark.The sample was then exposed uniformly to tungsten illumination to givean exposure of 400,000 foot-candle seconds to photodevelop the latentimage. The area given the latent image exposure was darkened to give areflection density of 1.25. The area receiving no latent image exposurewas darkened only slightly by the exposure of 400,000 foot-candleseconds, the reflection density being 0.33. The image discrimination ofthis photographic element was 0.92 density units (1.250.33). When theheat treatment step before the photolysis step is omitted, the entireemulsion area of the photographic element prints out to uniform density,there being no differentiation between image and nonimage areas.

These data demonstrate that a density ditference of the magnitudeusually associated with print-out papers can be achieved in a papergiven only a latent image exposure if the paper is heated to a hightemperature prior to overall photolysis.

Example 2 Two photographic elements of the type described in Example 1and treated as described in Example 1A and Example 1B were prepared anddesignated Element A and Element B in Table I below.

(a) Element A.Visi'ble image prepared directly with intensity imageexposure (a print-out image).

(b) Element B.--Visible image prepared 'by latent image exposure+heattreatment+photodevelopment (exposure in accordance with the invention).

Both Element A and Element B were exposed for 2 minutes to 1600foot-candles of illumination from a white flame arc lamp. The reflectiondensities of exposed and unexposed areas (image and non-image areas)were measured before and after the arc lamp exposure.

TABLE I Before arc lamp After are lamp exposure exposure Element A:

Exposed area. 1. 44 1. 55

Unexposed area 0.09 1. 46

Discn'minatiom 1. 35 0. 09 Element B:

Exposed area 1.25 1. 34

Unexposed area. 0. 33 0. 43

Discrimination 0. 92 0. 91

The data set out in Table I illustrates the improved light stability ofimages processed in accordance with the invention with a print-outphotographic system.

EXAMPLE 3 TABLE II Unexposed area Discrimination Platen temp, degrees F.

Exposed area The data in Table II illustrate that heating times of oneminute at temperatures of at least about 300 F. are used to achieve anysignificant image discrimination.

EXAMPLE 4 TABLE III Trivalent metal salt: Concentration (mg/Ag. mole)(NI-I RhCl 1.0 (NH RhCl 5.0 (NH RhCl 25.0 K IrCl 10.0

The various emulsions were coated on photographic paper supports, imageexposed, heated and thereafter photodeveloped to form visible images inthe areas of exposure as described in Example 1B.

The present invention thus provides a process for utilizing normallynonlatensifiable silver halide print-out materials for preparingphotodeveloped images having high stability.

The invention has been described in considerable detail with particularreference to preferred embodiments thereof, but it will be understoodthat variations and modifications can be effected within the spirit andscope of the invention as described hereinabove and as defined in theappended claims.

I claim:

1. A photodevelopment process for preparing visible silver photographicimages in a fine-grain silver halide photographic print-out materialcomprising silver halide grains which have trivalent metal ions occludedtherein, said grains having been formed in an acidic media, and whereinsaid silver halide grains have a halogen acceptor contiguous thereto;said process comprising imagewise exposing said silver halide to form alatent image, heating said exposed silver halide to at least about 300F. to repress printing out of unexposed areas of said silver halide andthereafter uniformly exposing said heated silver halide to light toproduce a visible silver image.

2. A process as described in claim 1 wherein said halogen acceptor is anitrogen-containing halogen acceptor.

3. A process as described in claim 1 wherein said trivalent metal ionsare selected from the group consisting of bismuth, iridium and rhodium.

4. A process as described in claim 1 wherein said trivalent metal ionsare bismuth ions.

5. A process as described in claim 1 wherein said trivalent metal ionsare rhodium ions.

6. A process as described in claim 1 wherein said trivalent metal ionsare iridium ions.

7. A process as described in claim 1 wherein said silver halideprint-out material is a gelatino silver chlorobromide emulsion in whichsaid silver chlorobromide has an average grain size of less than about.2 micron.

8. A process as described in claim 1 wherein said silver halide grainsare formed in the presence of trivalent metal ions.

9. A photodevelopment process for preparing visible silver photographicimages in a fine-grain silver halide photographic print-out materialcomprising trivalent metal ion-containing silver halide grains, saidgrains having been formed in an acidic media, and wherein said silverhalide grains have a halogen acceptor contiguous thereto; said processcomprising imagewise exposing said silver halide to form a latent image,heating said exposed silver halide to at least about 300 F to repressprinting out of unexposed areas of said silver halide and thereafteruniformly exposing said heated silver halide to light to produce avisible silver image.

10. A photodevelopment process for preparing visible silver photographicimages in a silver halide photographic print-out emulsion comprisingsilver halide grains having an average size of less than about .2 micronand having 4 occluded bismuth ions therein, wherein said grains areformed in an acidic media, and wherein said grains have a halogenacceptor contiguous thereto; said process comprising imagewise exposingsaid silver halide to form a latent image, heating said exposed silverhalide to at least about 300 F. to repress printing out of unexposedareas of said emulsion and thereafter exposing said heated silver halideto light to produce a visible silver image.

11. A process as described in claim 10 wherein said halogen acceptor isa nitrogen-containing halogen acceptor.

12. A process as described in claim 10 wherein said halogen acceptor isa thiourazole.

13. A process as described in claim 10 wherein said halogen acceptor isdithiourazole hydrazine salt.

14. A process as described in claim 10 wherein said silver halide grainsare formed in the presence of bismuth 15. A process as described inclaim 10 wherein the silver halide print-out emulsion is a gelatinosilver chlorobromide emulsion comprising at least mole percent bromide.

16. A process as described in claim 10 wherein the silver halideemulsion is coated on a paper support.

17. A process as described in claim 10 wherein said silver halideemulsion is coated on a polyethylene terephthalate support.

References Cited UNITED STATES PATENTS 2,448,060 8/1948 Smith et al96-108 2,717,833 9/1955 Wark 96-108 3,241,971 3/1966 Kitze 96-1083,287,137 11/1966 McBride 96-108 956,567 5/1910 Caldwell 96-1073,033,678 5/1962 Hunt 96-119 3,144,336 8/1964 Herz 96-108 FOREIGNPATENTS 1,177,004 8/1964 Germany.

NORMAN G. TORCHIN, Primary Examiner.

C. E. DAVIS, Assistant Examiner.

US. Cl. X.R. 96-107, 108

